Polishing pads including phase-separated polymer blend and method of making and using the same

Abstract

Polishing pads containing a phase-separated polymer blend, and methods of making and using such pads in a polishing process. In one exemplary embodiment, the polishing pads include a multiplicity of polishing elements integrally formed in a sheet. In another exemplary embodiment, the polishing elements are bonded to a support layer, for example by thermal bonding. In certain embodiments, the polishing pad may additionally include a compliant layer affixed to the support layer, and optionally, a polishing composition distribution layer.

The invention claimed is: 
     
       1. A polishing pad comprising:
 a sheet having a first major side and a second major side opposite the first major side; and 
 a plurality of polishing elements extending outwardly from the first major side along a first direction substantially normal to the first major side, wherein at least a portion of the polishing elements are integrally formed with the sheet and laterally connected so as to restrict lateral movement of the polishing elements with respect to one or more of the other polishing elements, but remaining moveable in an axis substantially normal to a polishing surface of the polishing elements, wherein at least a portion of the plurality of polishing elements comprise a first continuous polymer phase and a second discontinuous polymer phase, and at least one transparent polishing element affixed to a transparent portion of the sheet. 
 
     
     
       2. A polishing pad comprising:
 a support layer having a first major side and a second major side opposite the first major side; and
 a plurality of polishing elements, wherein each polishing element is affixed to the first major side by bonding to the support layer and each polishing element has an exposed polishing surface, and 
 wherein the polishing elements extend from the first major side of the support layer along a first direction substantially normal to the first major side, further wherein at least a portion of the plurality of polishing elements comprise a first continuous polymer phase and a second discontinuous polymer phase, wherein at least one of the polishing elements is a transparent polishing element. 
 
 
     
     
       3. The polishing pad of  claim 2 , wherein each polishing element is thermally bonded to the support layer. 
     
     
       4. The polishing pad of  claim 2 , wherein the support layer comprises a thermoplastic polyurethane. 
     
     
       5. The polishing pad of  claim 1 , wherein the second discontinuous polymer phase comprises a crystalline polymer, a thermoplastic polymer, a water soluble polymer, or a combination thereof. 
     
     
       6. The polishing pad of  claim 5 , wherein the second discontinuous polymer phase comprises at least one of a polyolefin, a cyclic polyolefin, a polyolefinic thermoplastic elastomer, poly(ethylene oxide), poly(vinyl alcohol), poly(vinyl pyrrolidone), polyacrylic acid, poly(meth)acrylic acid, and combinations thereof. 
     
     
       7. A method of making a polishing pad according to  claim 2 , comprising:
 forming a plurality of polishing elements comprising a first continuous polymer phase comprising a first polymer, and a second discontinuous polymer phase comprising a second polymer; and 
 bonding the polishing elements to a first major side of a support layer having a second major side opposite the first major side to form a polishing pad.